The present invention relates to antiperspirant compositions. Antiperspirant active is delivered to the skin by means of an anhydrous thixotropic cream vehicle containing particular concentrations of emollients and gelling agents.
Antiperspirant compositions in the form of creams are well known. Antiperspirant creams are commonly manufactured as oil/water emulsions with the antiperspirant active being dissolved in the aqueous portion of such emulsion compositions. While oil/water emulsions provide a convenient vehicle for storing and delivering antiperspirant actives, compositions of this type tend to produce an undesirable wet, cold and/or sticky sensation when they are applied to and rubbed into the skin.
The undesirable sensation produced by oil/water emulsion products can be minimized somewhat by utilizing compositions in anhydrous form. Anhydrous antiperspirant compositions can, for example, be produced in aerosol form (See Wahl; U.S. Pat. No. 3,725,540; issued Apr. 3, 1973); in semi-solid form (See Moore; U.S. Pat. No. 2,087,161; issued July 13, 1937) and in the form of a solid waxy stick (See the application of Elsnau having Ser. No. 632,128, filed Nov. 4, 1975, now U.S. Pat. No. 4,049,792, issued Sept. 20, 1977).
Anhydrous non-antiperspirant compositions in cream form are also known. An anhydrous medicament base, for example, is disclosed in Chang et al; U.S. Pat. No. 3,924,004; issued Dec. 2, 1975. Anhydrous rouge compositions are disclosed in Balsam and Sagarin; Cosmetics Science and Technology, 2nd. Ed., Vol. 1, Wiley-Interscience, 1972 in Chapter 11 at pgs. 355 - 358. Gelled ointment bases, emollients and polar liquids have been disclosed in Chen; U.S. Pat. No. 3,733,403; issued May 15, 1973 and in National Lead Company's Data Sheet B-18 entitled "Bentone 18-C" dated Jan. 31, 1962.
In spite of the above described prior art attempts, formulation of cream products in the form of anhydrous thixotropic gels is not accomplished without certain difficulties. Gelled compositions tend to exhibit syneresis, a bleeding or leaking of the gelled organic liquid from the gel structure or matrix. Further, such compositions may also tend to dry out or form crusts along those surfaces of the compositions which are exposed to the atmosphere.
Given the above-described problems and difficulties in providing antiperspirant products in cream form, there is clearly a continuing need for new and useful antiperspirant creams which are efficacious and which are aesthetically and cosmetically acceptable for sale as consumer products. Accordingly, it is an object of the present invention to provide anhydrous antiperspirant creams which do not impart an undesirable, cold, wet or sticky sensation when applied to the skin.
It is a further object of the present invention to provide such antiperspirant creams in the form of stable anhydrous trixotropic gels.
It is a further object of the present invention to provide such anhydrous thixotropic antiperspirant creams which exhibit minimal syneresis or bleeding of organic liquid from the thixotropic gel structure.
It is a further object of the present invention to provide such anhydrous antiperspirant creams which do not dry out or form unacceptable crusts upon prolonged exposure to the atmosphere.
It has been surprisingly discovered that the above objectives can be realized and superior antiperspirant creams provided by formulating anhydrous thixotropic creams utilizing particular amounts of certain types of emollients, suspending/thickening agents, gel promoting agents, and antiperspirant actives.